Bangladesh cholera vaccine trial

By Dr. Ananya Mandal, MDFeb 20 2011

Bangladesh will conduct the world’s largest clinical trial of an affordable cholera vaccine which could save tens of thousands of lives. The study began Thursday and involves nearly 250,000 people near the capital, Dhaka.

If the results are encouraging, the programme can be replicated in other countries where cholera is a big problem, health officials say. Bangladesh loses hundreds of people to cholera outbreaks every year during the monsoon. At present many oral vaccinations are considered too expensive for millions of people in this impoverished country. This new vaccine is one-tenth of the cost of the current available vaccines. Two-thirds of the 250,000 people involved in the trial will receive two doses of the Indian-made vaccine. The remainder will not receive the medicine and the two groups will be monitored over the next four years.

Firdousi Qadri, one of the scientists involved in the project said, “It is a study that will demonstrate that we can deliver the vaccine to the population that needs it the most, the people at high risk of cholera… At the same time it will be a test of the existing immunization mechanism that we have in this country.” The study will also find the exact number of people dying from the disease and if the programme proves successful, then the authorities will go for a mass immunization of the entire country. Other vulnerable countries like Haiti may benefit from this vaccine.

“It’s the biggest cholera vaccination study in the world,” said Nasmeen Ahmed of the International Center for Diarrhoeal Diseases Research, Bangladesh (ICDDR'B), which is running the scheme with the government. “A successful outcome could prompt governments in countries where cholera has been a big health problem to go for a mass vaccination drive…It is a critical study to know how a government can vaccinate millions of people against cholera,” she said.

Cholera is water borne disease that is caused by bacteria and may lead to severe dehydrating diarrhea and in most cases – death. The World Health Organization estimates that up to five million people worldwide contract cholera each year, with 120,000 of them dying as a result. Some experts say that along with mass vaccination, investments in improved water and sanitation infrastructure can help reduce the impact of cholera.